[en] Using the SWIFT-transport code a radial injection, dual-tracer test was modelled. This case is based on a field test carried through in a sand aquifer. Monitoring the tracer migration and analysing the break-through curves result in effective dispersivity values and distribution coefficients. These data are used to fit the tracer concentrations calculated by the SWIFT-model to the measured ones. An inexact fit may depend on the simplification of the real situation to that of a homobeneous aquifer with a variable discharge rate with depth. The calculations show that generally a case like this can easily be handled by the SWIFT-code. Dispersivity values in the range of 1 cm, however, will lead to a very detailed discretization if it is desirable to avoid numerical dispersion. (orig.)